The present invention relates to liquid-dispensing apparatus, and particularly to apparatus useful in the remote-controlled dispensing of a foamable liquid such as beer.
In beer-dispensing systems, undesired beer foaming can be minimized by opening the dispensing valve rapidly, and closing the same at a slower rate, substantially that of fluid flow into and through the valve. In manually-operated dispensing systems, such valve operation may be accomplished by use of a beer valve designed to operate between partially opened and fully closed conditions primarily under the influence of fluid flow through the valve. This type of valve may be placed quickly in a fully opened condition through rapid manual operation of a valve-controlling lever. To close the valve, the lever is manually operated to place the valve in a partially opened condition, whereat fluid flow through the valve is effective to produce valve closing, substantially at a rate determined by fluid flow through the valve.
The above-described manual operation contrasts with the operation of remote-controlled beer-dispensing systems known in the prior art. Commonly, such remote-controlled systems employ an in-line solenoid valve designed to produce rapid valve-opening, e.g., within about ten milliseconds. However, the opposite (valve-closing) solenoid movement which occurs at the same speed creates, by such speed, a water-hammer effect on the beer, causing undesired foaming.
The in-line solenoid valve also generates heat during solenoid operation, this heat being partially transferred to the beer, undesirably increasing its temperature and lowering its gas solubility. Also, because the electrical solenoid is located near the bear-dispensing nozzle, the potential for short circuiting and/or electrical shock in the region of the beer dispenser is present.
A general problem associated with beer-dispensing systems is valve sticking, or locking, which may occur after periods of valve disuse, and which results from the sticky residue formed by dried beer. When valve locking occurs, it may be necessary to impact the valve to initiate opening. Impacting is inherently difficult to achieve with the in-line solenoid system of the type mentioned above.
It is an object of the present invention to provide a remote-controlled valving apparatus, the valve of which can be opened rapidly, and closed at a rate which is dependent on the rate of fluid flow through the valve, i.e., which can be operated in a manner similar to the above-described manually-controlled valve.
It is yet another object of the invention to provide a beer-dispensing valving apparatus operable throughout a wide range of liquid-supply pressures.
Another important object of the present invention is to provide a remote-controlled valving device employing a lever-operated valve, wherein the lever is impacted upon initiation of the valve-opening operation.
Still another object of the invention is to provide a liquid valving device which utilizes a conventional type of beer valve by a simple adaptation thereof.
The present invention is gas-controlled valving apparatus includes a valve having a plunger movable between opened and closed conditions, and a shiftable lever operable to move the plunger between such conditions. Attached to the valve is a pneumatic ram or pump operable, upon supply of pressurized gas thereto, to shift the lever to produce movement of the plunger from its closed to its opened position. The pneumatic pump is coupled to the lever by a clevis attached to the pump and dimensioned to permit play in the relative movement therebetween. By this construction, the lever is substantially impacted by the clevis upon initiation of valve opening.
A spring interposed between the pump and the lever, with gas exhausting from the pump, initiates shifting of the lever to produce movement of the plunger from its opened toward its closed condition, primarily under the influence of the spring. Liquid flowing through the valve acts on an upstream surface defined on the plunger, which cooperates with the spring to complete movement of the plunger toward its closed condition--with such completing being primarily under the influence of fluid flow through the valve.
These and other objects and features of the present invention will become more fully apparent when read in connection with the following detailed description of a preferred embodiment of the invention, and the accompanying drawings.